JQ-100 standard COD digester (6 tubes)

product overview： JQ-100 type standard COD digester (6 tubes)）Following the new national standardsHJ 828-2017Replace（GB 11914-89）The standard analytical method has standardized the development of chemical oxygen demand for water qualityCOD（Cr）The measurement steps strictly specify the heating and digestion time of the method, ensuring reflux heating and slight boiling2The digestion operation for hours, the preparation and addition of reagent solution are consistent with the national standard methodEnsure reliable and accurate analysis results. JQ-100 type standardCODThe digester can achieve the goal of saving water, reducing power load, and improving efficiency for enterprise users.

Product Features： JQ-100 standard COD digesterMainly composed of body, reflux pipe, fan, electric furnace plate, etc4Most of the components are controlled by microcomputer technology for timed heating of the electric furnace plate and fan, which can6Simultaneously heating the conical flask reflux device.Standard COD digesterUsing glass burr reflux pipes instead of spherical reflux pipes, and replacing tap water cooling with air cooling technology. The cooling part is mainly completed by burr condensation tubes and fans. The upper part of the condensation tube is spherical, and the catalyst is added from here to prevent the instantaneous volatilization of light components in the sample. The lower part is“burr”Shape, protruding from the wall of a condenser tube on a plane3individualFacing each other“Cold Bubble”Larger cooling area than a simple spherical condenser tube，And it can block the passage of volatile substances and vapors, coupled with the dual effect of cooling water in the upper spherical reflux tube and the fan inside the machine, ensuring the reflux cooling of the sample.

technical specifications：

Measurement range: 10-700mg/L (measured after dilution of water samples greater than 700mg/L)

Measurement time: no more than 2 hours

Measurement error: Potassium hydrogen phthalate standard solution (500mg/L), relative standard deviation not greater than 5.0%, industrial organic wastewater (500mg/L), relative standard deviation not greater than 8.0%

Environmental temperature: 5-40 ℃

Heating power: 1200W (AC 220V ± 22V, 50HZ)

Specific operating steps:Add 10ml of sample to a 250mL conical flask with a standard grinding mouth of No. 24, then add 2mL of mercury sulfate solution, followed by 5.0mL of 0.250mol/L potassium dichromate standard solution and several explosion-proof boiling glass beads. Shake well. Connect the conical bottle to the lower end of the burr condenser tube. Slowly add 15mL of silver sulfate sulfuric acid reagent from the top of the condenser tube to prevent the escape of low boiling point organic matter, and continuously rotate the conical flask to mix it evenly. Reflux the solution for two hours from the beginning of boiling. After cooling, rinse the condenser tube with 45mL of distilled water from the upper end, and then remove the conical flask. After cooling the solution to room temperature, add 3 drops of 1,10-phenanthroline indicator solution and mix evenly. Titrate with ammonium ferrous sulfate standard titration solution, and the endpoint is when the color of the solution changes from yellow to reddish brown after blue-green. Record the consumption volume of ammonium ferrous sulfate standard solution and calculate the result according to the method standard.